This invention relates in general to the production of a fluid lime suspension and, in particular, to an apparatus for producing such a suspension.
The advantages of periodically applying fine limestone to farm land are well known. In particular, the periodic application of limestone to farm land raises the PH (makes it less acidic) of the soil and provides to the soil essential secondary nutrients such as calcium and magnesium. By properly controlling the PH level of the soil in this manner, it is possible to greatly enhance the effectiveness of any fertilizer which is applied to the soil, thereby making the land more productive.
It has been determined that the best results are obtained when the lime is applied to the soil in the form of a finely ground powder. Coarse or granular limestone is insoluble and requires many years to react and adjust the PH of the soil. By applying the limestone to the soil in the form of a fine powder, the limestone dissolves in a shorter period of time and provides more accurate control of the PH of the soil.
The application of limestone to the soil in the form of a finely ground powder, however, presents several problems. One of the major difficulties is to prevent undue generation of dust and the associated air pollution problems. Another difficulty is that it is difficult to insure uniform application of the powdered lime to the soil.
The above mentioned problems can be effectively eliminated through the use of fluidized lime. Fluidized lime is comprised of a liquid slurry wherein a lime particulate is suspended within a fluid medium. The fluid medium is normally comprised of a suspending agent such as attapulgite clay and water or liquid nitrogen.
Fluidized lime is typically produced by mixing powdered lime with the fluid medium in an open tank which is equipped with a mixing blade and circulating pump. In performing this technique, the fluid medium is initially added to the tank. Thereafter, the powdered lime is simply poured into the tank and dispersed through the fluid medium by the movement of the mixing blade.
This technique for producing fluidized lime, however, has not proved to be totally satisfactory. In particular, performance of the above mentioned technique causes a large amount of dust to be generated when the powdered lime is poured into the mixing tank. This dust creates an air pollution problem which is highly undesirable from an environmental standpoint. In addition, the above mentioned technique does not always provide uniform mixing of the lime powder within the fluid medium.
It is therefore an object of the present invention to provide a method and apparatus for producing fluidized lime wherein powdered lime is mixed with the fluid medium in a closed system, to thereby eliminate the problem of air pollution.
Another object of the invention is to provide a method and apparatus of the character described in which the fluid medium and the powdered lime are thoroughly and uniformly mixed.
An additional object of the invention is to provide an apparatus of the character described which is capable of receiving powdered lime from a pneumatic trailer to facilitate handling thereof.
It is an additional object of the present invention to provide an apparatus of the character described which is capable of producing fluidized lime quickly and easily.
Other and further objects of this invention, together with the features of novelty appurtenant thereto, will appear in the course of the following description.